The woman walked into the crowd at the main gate of the Muqdadiyah police
station, according to a police officer at the scene who spoke on condition of
anonymity because he was not authorized to speak to the media.

At least 16 people were killed and 33 wounded, according to Dr. Abdul Salam
al-Jibour at Muqdadiyah General Hospital. Muqdadiyah, a mostly Sunni Muslim
city, lies about 60 miles northeast of Baghdad.

Meanwhile, U.S. and Iraqi army forces were engaged in fierce fighting with
gunmen in two Sunni-dominated neighborhoods of the capital, Fadhil and Sheik
Omar, police and witnesses said.

An American helicopter involved in the battle came under ground fire but was
not shot down, a senior U.S. military official said. He spoke on condition of
anonymity because U.S. officials were still investigating the incident.

Police said one person was killed and 14 wounded in the crossfire. Repeated
artillery fire rang out across Baghdad at midday Tuesday, but the target was
unclear.

Also Tuesday, the U.S. military announced the deaths of four U.S. soldiers
three killed by a roadside bomb in Baghdad and another killed in combat in
western Anbar province.

The three were killed Monday by a roadside bomb and a secondary explosion
while on patrol in a southeastern section of the Iraqi capital, the U.S.
military said in a statement.

The unit had been conducting raids against militants in the area, and had
recently captured five suspects, it said.

Another U.S. soldier was killed the same day while conducting combat
operations in Iraq's western Anbar province, another statement said.

At least 3,285 members of the U.S. military have died since the beginning of
the Iraq war in March 2003, according to an Associated Press count. The figure
includes seven military civilians.